From: Tim Jiang tjiang@codeaurora.org
stable inclusion from linux-4.19.198 commit 012a3944008fc774b1eae42be7e8dfc4ee2ab521
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[ Upstream commit 4f00bfb372674d586c4a261bfc595cbce101fbb6 ]
This is btsoc timing issue, after host start to downloading bt firmware, ep2 need time to switch from function acl to function dfu, so host add 20ms delay as workaround.
Signed-off-by: Tim Jiang tjiang@codeaurora.org Signed-off-by: Marcel Holtmann marcel@holtmann.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/bluetooth/btusb.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index 1b0adf5c23760..7188f0fb2e050 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -2595,6 +2595,11 @@ static int btusb_setup_qca_download_fw(struct hci_dev *hdev, sent += size; count -= size;
+ /* ep2 need time to switch from function acl to function dfu, + * so we add 20ms delay here. + */ + msleep(20); + while (count) { size = min_t(size_t, count, QCA_DFU_PACKET_LEN);